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Long-Term Investments - Additional Information (Details) $ in Thousands | 12 Months Ended
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Dec. 31, 2019 CNY (¥) Investment | Dec. 31, 2019 USD ($) Investment | Dec. 31, 2018 CNY (¥) | Dec. 31, 2017 CNY (¥)
Schedule Of Equity Method Investments [Line Items] |  |  |  |
(Loss) gain from equity method investments | ¥ (136,000) | $ (20) | ¥ 1,710,000 | ¥ (4,890,000)
Impairment loss | ¥ | ¥ 0 |  | ¥ 0 |
Limited Partnerships |  |  |  |
Schedule Of Equity Method Investments [Line Items] |  |  |  |
Number of investments | Investment | 3 | 3 |  |

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